The debate over the Viaduct and the proposed deep-bore tunnel solution has reached what politicos call "saturation." The issues have been so thoroughly debated that voters are saturated with information and have plugged their ears. This explains, for example, why Mayor Mike McGinn's former key issue, the cost-overrun factor, has dropped from sight.

Instead, the final days of the campaign leading up to the August 16 vote on Seattle Referendum 1 (yes means go ahead with tunnel, no means tossing a modest monkey wrench into the juggernaut) will be aimed at pushing some simplistic buttons for the few remaining undecideds, and launching attacks that slice through the saturation.

For the opponents of the Big Bore, this means rallying Viaduct-rebuild advocates in West Seattle, Ballard, and Magnolia, tapping the strong local opposition to tolls (a tricky issue since greens favor tolls), disparaging the big-money interests behind the tunnel, appealing to fiscal conservatives who fear a Boston-style Big Dig, and summoning young greenies to strike a blow against cars and old-fogies transportation planning.

For proponents of the Big Bore, there are two big buttons to push. One is that, regardless of the merits of the plan, it's time to move forward, so let's stop all this dithering and plunge ahead with the one plan still standing, risky as it may be. (A corollary: if we scuttle the tunnel, we'll have another decade of debate to find a new "solution.") The second button/argument is that tunnel opponents are providing aid and comfort to Tim Eyman (now running an initiative against tolls and Sound Transit, though actually he tells me he's ambivalent about the tunnel) and "Mayor Gridlock."

One unspoken issue is Mayor McGinn's future political prospects. McGinn is lying low on the Big Bore, at least for now. He grasps that this issue is dragging down his popularity, so he's lately been talking about all kinds of new issues (coal trains, sex ads in Seattle Weekly, school levies) in a commendable effort to broaden his appeal and soften his obstructionist image. Similarly, the campaign against the tunnel knows that McGinn is a liability, and so it is also shunning the mayor. Not so the tunnel backers, who will try to make McGinn an issue by turning the race into a plebiscite on McGinn, weakening his chances of re-election.

Another looming issue is this: If the Big Bore is rejected decisively by the voters and the City Council and the state defiantly plunge ahead with the project, they risk the "Safeco Syndrome." That refers to the time when a large facility was constructed despite a narrow public vote against it — producing decades of voter anger.

So how did we get into such a Big War over what might otherwise be thought of as a complex engineering question modestly affecting a small part of the overall transportation system? To answer that we need to explore some recent civic history.

It might have been a simple saga. The earthquake in 2001 weakened the Viaduct enough to make the case, finally, that it had to be replaced or torn down. The legislature, surprisingly, was willing to fund a very expensive, very Seattle project (in part because SR 99 really is the blue-collar highway to industrial and Port-related jobs to the north and south of Seattle). But then it got verycomplicated.

The first complication arose around 2003 when the Seattle design community and downtown interests hatched (revived, really) plans for a grand waterfront park, leveraging state dollars to get this amenity. Speaker Frank Chopp was not pleased by this added expense, and seems to have gone into opposition early on. (One view of the infamous cost-overrun amendment, which Chopp may or may not have engineered, is that it was put in there to stop Seattle from loading on still more requests of this sort. At any rate, Chopp has been the bane of everyone's existence on this issue. )

The next complication was that Gov. Gregoire, who favored building a new viaduct, and Mayor Greg Nickels, who wanted a cut-and-cover tunnel with a park on top, could not resolve their differences and grew openly hostile to each other and more entrenched in their positions (Nickels wanting a park, Gregoire wanting a new viaduct).

A third complication was that Seattle progressives split, with the Coalitionists (led by Allied Arts) willing to keep the current through-put capacity for cars (the state's bottom line demand), while the Rejectionists, led by Cary Moon and later Mike McGinn, pressed their agenda for de-highwaying Seattle as old freeways crumble, thereby accelerating the shift to transit, bikes, and urban density.

The fourth complication was a split in the business community, with downtown interests led by the Downtown Seattle Association willing to trade off through-put capacity on SR-99 if that's what it took to get a waterfront park, and the Greater Seattle Chamber of Commerce (pressed by Boeing and the Port) insisting on preserving car and truck mobility.

So what looked at first like a dream political coalition — labor (wanting the construction jobs), business (wanting an urban amenity to stimulate development and tourism), design advocates wanting a world-class waterfront park, and environmentalists (restoring some of the waterfront to natural, salmon-happy conditions) — was in fact a great big dysfunctional, feuding family. Over the years, these internal wars bruised feelings and friendships, making compromise ever more elusive.

Many of these fractures eventually healed. Around 2007, the downtown interests and the regional business interests agreed to work together. Chopp was isolated after his tactical error of introducing an unpopular plan (the "Choppaduct") of his own. The same might be said of King County Executive Ron Sims, who marginalized himself by daring to oppose Sound Transit 2's bond issue. The left-liberal civil war just got worse (as usual). And the mayor and the governor grudgingly found a way to a common position.

The way to that compromise was a minefield, however. The first escalation of the war was an advisory vote in 2007, where voters rejected both the Nickels' cut-and-cover tunnel (70 percent against) and the governor's new-viaduct scheme (57 percent opposed). Gregoire was facing a re-election year in 2008, so wanted to avoid forcing the issue and offending some Seattle voters. An artful device was deployed where the city and the state departments of transportation decided to do elaborate (and often quite good) studies, and a broad-based stakeholders' group was enlisted to advise. Nickels and Gregoire agreed to shut up on the subject all during 2008, and to see if a solution would somehow emerge. Oddly enough, the solution did materialize, though not one to end the hostilities.

Gregoire always opposed the surface-transit solution (a plan calling for no viaduct and no tunnel but with new transit and various ways of diverting traffic to I-5 and downtown streets). Mayor Nickels, after seeing his cut-and-cover tunnel idea shot down by that 2007 vote, shifted toward the surface solution as seemingly the only alternative to building a new viaduct. Grace Crunican, the forceful director of the Seattle Department of Transportation, also became increasingly positive about the surface/transit/I-5 solution, while her planners also kept exploring a tunnel option. State continued to work on all options, and both parties interpreted the 2007 vote as taking the viaduct off the list and looking for options that were not on the ballot, namely surface and a tunnel that wasn’t built by cut and cover.

Gregoire got reelected in November 2008 and the political logjam quickly got unstuck, but in a messy way. Tim Ceis, who was deputy mayor to Nickels through all this, related to a Crosscut writers' meeting last week that Crunican ultimately informed Nickels privately that "the surface solution won't work." For whatever reasons, Mayor Nickels drifted from the surface solution to the Big Bore, though this put him in a bad political position with the advocates of the surface solution, who counted on him.

Crunican's recollection is more complex than Ceis's blunt summary, though not essentially different. Still living in Seattle after Mayor McGinn declined to keep her as head of SDOT, Crunican told me in an interview this week that the surface solution could have worked, technically, in terms of capacity to move people, but not at all well in terms of capacity to move vehicles. Even then, the plan would have required some overly generous actions on the part of the state and King County to fund a very robust increase in transit primarily serving Seattle. For the no-viaduct, no-tunnel solution to work you would have to add a lot of new transit, she explained. Downtown Seattle, hemmed in by hills, water, and a narrow waistline, is "a hell of a place to serve" with more surface transit. We can see now, with Metro dramatically cutting service and its promised Bus Rapid Transit routes curtailed, how risky it would have been to count on Metro, even without a recession.

As for the state, one of the growing improbabilities was that it would find the money (and the political will) for an elaborate reworking of I-5 to take some of the traffic displaced by the loss of the Viaduct. Ramps would have been closed to midtown, to recapture through lanes, for instance. Given how squeezed the state is for roads money, and how unpopular Seattle is in Olympia, Crunican calculated, probably rightly, that this second key component of the surface plan was very problematic.

And so in the end, "I couldn't make the surface solution work better than the deep-bore tunnel," Crunican recalled. "This is not to say that the surface plan couldn't have worked, given a state willing to go along and a city, like Stockholm or London, willing to do dramatic things in controling cars in downtown."

Crunican adds that the work done in trying to make the surface solution work ended up being of great value in making the Big Bore work. She cites steps such as the Fourth Ave. loop south to Spokane St., redesigning Mercer to bring back the grid system, adding bike lanes, and making transit nodes out of King St. Station, the Ferry terminal, and Westlake Square. In fact, the surface advocates, thanks to Crunican, made a lot of progress in reorienting Seattle to more bus and bike lanes. She also thinks the city was a clear winner in its biggest goal: preventing the building of a new viaduct.

Cary Moon, the chief advocate for the surface solution, praised Crunican highly just before Mayor McGinn replaced her in 2009. Crunican was the one, Moon wrote in Publicola, "who figured out how to make surface/transit work by increasing transit, fixing the street grid, and changing transportation policy. She had the technical chops to figure out a very complex system, the leadership skills to reorient her boss (that would be Greg Nickels) and staff, and the political smarts to get our statehighway department, for God’s sake, to go along with highway removal."

Almost.

Like Nickels, Gov. Gregoire also moved into compromise territory. In December, 2008 the state DOT issued its two low-bid recommendations of either a rebuilt viaduct or a surface/I-5 option, saying these two options were the only ones that fit within its $2.4 billion budget.Seeing a new viaduct rise from its grave stunned the Stakeholders Committee and others eager for a waterfront park. This was the point when the tunnel advocates pushed back hard, convincing WSDOT to look again at the tunnel, now a single-bore proposal that saved money over the original double-bore version. In making this case, key players were Tayloe Washburn of the Chamber of Commerce, Dave Freiboth of the Labor Council, Ivar's CEO Bob Donegan, and Bruce Agnew of the Discovery Institute, which had hatched the deep-bore idea. Seattle City Councilwoman Jan Drago played a key backstage role, laying the political groundwork for Mayor Nickels' big shift.

The Big Bore came to the rescue, once it became (or seemed) financially feasible. It allowed the construction of the tunnel to take place while the old Viaduct remains standing (earthquake gods willing), avoiding years of maddening detours if the Viaduct had to be demolished first to make room for a new one. The tunnel provided more open space for the waterfront park, which Gregoire was finally coming to appreciate. It provided two lanes each way for tunnel traffic, responding to the need for vehicle-traffic through-put and placating big employers such as Boeing.

It was time for the key elected officials to make a decision, "leading from behind," as it's called. They got together in the Seattle City Hall conference room, and, according to one source who was present, Gregoire went around the room and asked each person for his or her recommendation. County Executive Ron Sims stuck with the surface solution, understandably wanting to drive more people to the Metro Transit system the county runs and eyeing the additional revenues. (Keep this in mind if Sims runs for mayor, perhaps pulling in some of McGinn's support.) Drago, a key dealmaker (as was then County Councilmember Dow Constantine) broke the ice by daring to favor the Big Bore. Nickels, the last to speak according to this source, surprised the room by saying he might be able to accept the tunnel solution.

And so the deal was reached, quietly and mysteriously. The secrecy quickly produced a deep feeling of betrayal and suspicion on the part of the surface advocates (and viaduct proponents). The dealmakers decided to portray the decision as Gregoire's alone, providing some political cover for Nickels, but further confusing the public. In hindsight, it might have been better if Nickels and Crunican had fessed up publicly about the perfectly sensible reasons for their change of mind.

Another part of the big deal was a promise that Metro Transit would get more taxing authority from the Legislature, a promise yet to be kept but enough to get Sims to sign the peace treaty in January 2009. Here, too, the final deal seems fumbled, open to conspiratorial theories, and turning the losers into die-hard opponents. In fact, Sims would have been foolish to think the legislature, thoroughly tired of Seattle and this issue (and him), would have ponied up money to make the surface solution, an idea widely derided in Olympia, work.

Some day, all of this will make an absorbing case study in how big decisions are made. It certainly wasn't elegant. All during 2008, while Gregoire declined to make a decision that would have cost her some votes in a critical reelection campaign, the transportation bureaucrats, citizens, and armies of consultants circled warily in a kind of void. That leaderless year raised false hopes for the surface solution and left the transportation departments to push for competing solutions and to mind-read the mayor and the governor.

Oddly, though, the Stakeholders Committee turned out to be the surprise best idea of the whole saga. The year of study did enable the ultimate leading solution, the Big Bore, to emerge. When it suddenly became the best political solution, however, there wasn't a lot of time to study it. The winner emerged as mostly a political solution whose main claim was that it was better than the other two, with engineering and cost studies to follow.

Ultimately, the central question, even if the surface/transit/enhanced I-5 solution had survived technical scrutiny (as it almost did), was whether it was politically viable. Gregoire never seemed open to it, and she held the trump card since the SR in SR-99 stands for "state route." Speaker Chopp, a foe of Mayor Nickels, would have been another formidable obstacle. Already in early 2009, when the decision was made, we were plunging into a scary recession, drying up the funds needed from the state for I-5 and from Metro.

Given all this, it would have made sense for the governor and the mayor to work out their deal much earlier, rather than trying to please various factions with kind words and so many studies that nearly every position ended up citing "proof."

The clumsiness and secrecy of the ultimate deal provide one explanation for the continuing Big War. The larger reason is that the conflict is also a fundamental and deeply significant debate over the kind of city Seattle aspires to be

For younger people, for workers in the knowledge/technology industries, for newcomers with sophisticated versions of leading-edge cities such as Amsterdam or Barcelona in mind, Seattle should realize its destiny as a new-economy, highly educated, talent-magnet, youthful world city. That means rail transit, not cars; bikes, not beltways; go-go technology companies, not sleepy behemoths; urban density and streetlife, rather than quasi-suburban single-family neighborhoods; and a city resigned to high costs.

For others, Seattle is that rare city that has a chance to retain and grow a balanced workforce and diversified economy, keeping a healthy manufacturing and Port sector and providing affordable middle-class living, while also embracing the globalized creative economy of Amazon and biotech. Let other cities such as San Francisco casually jettison their ports (sending the ships to Oakland), price out a less-educated workforce, and densify- and tax-out young families who crave yards and cart kids around in station-wagons.

These are hard views to reconcile, in part because there are so many class issues lurking in the debate. One way, therefore, of seeing the bitter political warfare over Mayor McGinn, beyond the tunnel debates, is that he is very clearly a mayor of the bikes/transit/nightlife/new economy side, while Mayor Nickels was (or perceived to be) a last hurrah for the city that Boeing built. The transition was too abrupt — just as the influx of those with this new outlook has been too large — for easy digestion.

The Big Bore is a powerful and worthy symbol of this deeply important conflict. Particularly in Seattle, highway issues tend to galvanize debates over these generational and value shifts, in part because large infrastructure projects can last for decades. And in Seattle, we escalate straightforward issues of transportation or urban architecture into broad cultural wars over the soul and destiny of the city. (Examples: saving Pike Place Market, defeating the Commons, blocking the R.H. Thomson Expressway.)

It is also maddeningly difficult to resolve successfully these value-laden civil wars. The 2008 peace treaty over the Viaduct has not held. Will there be another chance to do so after the August 16 vote? Possibly. If the voters ratify the Big Bore, Mayor McGinn or a new mayor might find a way to change the subject without discrediting the losing side and its highly intelligent critique of the old, auto-centric ways of planning cities. A good example is the way former City Councilmember Peter Steinbrueck puts it: he's not particularly fond of the tunnel, but eager to get its benefits, notably that grand park and more urban density, out of the deal.